Tool holder for grindstones



Aug '19, .1930.

c. E. DAVIDSON 1,773,448

TOOL HOLDER FOR GRINDSTONES Filed Nov. 25, 192'? 2 Sheets-Sheet l gwve'ntoa 6/1 a r265 fiava'dismz/ Aug. 19, 1930. c. E. p-Avlbs N 1,773,443 I TOOL HOLDER FOR GRINDSTONES Filed Nov.'25, 1927' I 2 Sheets-Sheet 2 Elm pewter,

' V holder. 1 I

Patented Aug. 19, 1930 CHARLES DAVIDSON, F crim'roivdinmnors I "i 'roor. HOLDER FOB enmns'roivns v Application filed November 25,1927. dSerial No. 235,692.

This invention relates to tool holdersfor grindstones, and has for its object to provide a device for holding shear blades or other edged toolsor articles against a rotary grind- 111g wheel at a desired angle and permitting the article'to be moved nan accuratepath for the grinding operation.

A further object of the invention is to provide a holder of the character described I whereby shear blades or other articles may be ground with any desiredbeveland accurately 'uided so as to avoid liability of injury to the point of the blade in its movement across the face of the grinding wheel. I 'The invention consists of the features of construction; combination and arrangement of parts, hereinafter fully described and claimed, reference being had to the accompanying drawings,in which I "Figure 1 is a'view' in sideelevation ofa grinding wheel, showing the application of the inventio'n thereto. f I I Figure Q'is a view-in rear elevation of the Figure 3 is a side view of a portion ofthe grinding wheel, showing a shear blade in section" and at the angle it is held forthe grinding operation. v V I 1 Figure 1 is a front-to-rear sectionjthrough the tool holder, looking "toward one end thereof; v I l v I I I Figure 5 is a view similar to Figure 4, looking toward the opposite end of the holder." f P j Figure '6 is a sectional viewthrough the slidingtool' carrier bar and its tool clamp and sh'owing'a shear bladeclamped i'n position thereby; i I

Figure 7 is aperspec'tive View of the tool Figure 8-is a perspective view of thesliding 'tO'Ql ca'rrier bar. I it v J Figure 9 is a perspective view of am0difiedform of't'ool holder.

In carrying my invention into pra'ctice I provide a tool holder 1" in the form of a sub? stantiallywinvertedf u-shaped bracket. said bracket comprising a" top bar or plate- 2 and depending arms 3 and 4.. The arm 30f the i 5 bracket isof-greater length than and depends,

below the arm e and is'provided at its lower end with a slot 5 for-adjustable engagement with a support 6 onthe frame of agrinding wheel 7 ,which support 6 is provided with a screw clamp '8 to engage theflarm 8 and clamp it in adjusted position against said support. The slot 5 allows'the holder 1 to be adjusted, for prop'erworking relationship to the grinding wheel 7. or for coaction with grinding wheels ofdiiierent diameters. 1 l

The top plate 2 of the holder 1 is'formed with a longitudinal slot amending its full length and'opening through its ends and cornmunicating' at its 'oppositeends with slots 10 andllformed in the arms 3 and d. The slots 10 and 11 provide seat slots and guides for the reception of a sliding tool carrierbar 12 which is reciprocable therein for moving the article te be sharpened across the face. of the grinding wheel; the slo't 9 forming a trans verse slot to permit thebar' l2to be slipped iiito and-out ofe'ngagem'ent with the slotslO and 11,' as will be readily understood. The bar-12 is of suitable lengthfor the purpose andprovided at one end withanarticle clamp coniprisinga fiXedo'lamping member'13 and an adjustable clamping member 14 A bolt 15 passes through the" bar and through an clamping member, 1d may be adjusted and held 'fiXed to clamp the article against the member 13. {The member 13 has its clamping face provided with gaugepins' 17 or the like against which one surface of the article to beelampedmay bear to properly center said article in position. In the present in-; stance the device as shown in Figures '2 and V 6 isemployed for clamping'a shear blade18 position forthe'sharpening of its cutting i';

I The slot' 10 isjof'a depth" coinciding substantially with the depth of thebar 12, so that it will just snugly jrece'ive said bar-and permiti ofitsea'sy sliding movement, while the'i slot' ll is of mu'chigreater depth'than the bar so as to permit-thebar to be disposed at I dilfe'rent workin'g angles for proper adjustment Of the article ,with'relation to the face of the grinding wheel 7 and to enable the ar 109 V invention ticle to be disposed so that edge surfaces of articles having diiferent bevels may be accurately ground. For the purpose of holding the bar from displacement in the slot 10 a latch 19 is provided. This latch is pivotally mounted, as at 20, upon the arm 3 for movement toward and from the slot and is provided with a guard finger 21 arranged to overhang the slot 10 when the latch is in working position. At its lower end the latch is provided with a lug 22 movable in a segmental guide slot 23 inthe arm 3 and connected with the arm by means of a coiled spring 24 normally acting to hold the latch in slot closing position. When in such position the finger 21 cooperates with the walls of the slot 10 to form a guide for the bar 12 whereby a straight line motion of the bar isensured. For the purpose of supporting that portion of the bar lying in the slot 11 an adjustable seat rest 25 is provided. This comprises an L-shaped member pivoted to the arm 4, as at 26, and embodying an arm 25 normally extending at an angle across the slot 11 and an arm 25 engaged by an adjusting and set screw 27 whereby the arm 25 may be vertically adjusted and held in adjusted position. The upper edge of this arm 25 forms a support against which the lower edge of the bar rides, as shown in Figure 5, and affords a means by which the bar may be supported and guided at this point at any working angle. By adjustment of'the rest 25 the bar may be set at the proper angle for the grinding of a beveled surface of a shear blade or other article by movement of the blade across the face of the grinding wheel in such manner that the point of the blade will be guided and prevented from striking against the damaged, in the event that in the reciprocating movements of the bar the blade is moved beyond the grinding surface, as will be readily understood. a

The operation of the device will be apparent to those versed in the art from the foregoing description, and it will be seen that the provides a type of holder by means of which shear blades and other articles may be mounted upon a grindingwheel for a sharpening action and operated so as to be sharpened in a ready and expeditious manner, and that the construction is such that the article may be held at any working angle with relation to the face of the grinding wheel and disposed for the sharpening of beveled cutting surfaces of any degree.

In Figure 9 I have shown a modified type of holder l in whichthe construction is generally the same as that of the holder 1, except that the arms 8 and 4 areofthe same length and the slot 5 omitted, and both arms 3 and 4& provided with slots 5 which are inclined or extend at an oblique angle tothe plane of the arms. This construction of side of the wheel and becoming.

holder is for application to grinders having a pair of spaced tool supports with which the slots 5 may be engaged, the inclinationof the slots adapting the holder 1 to be adjustable to vary the grinding angle or to adjust the article with relation to the grindstone where grindstones of different sizes are used.

Having thus fully described my invention, I claim 1. A holder for tools to be ground comprising a substantially inverted U-shaped bracket embodying a top plate and'depending arms, said arms being provided with bar receiving slots, the slot of one arm being deeper than the slot of the other arm and the top plate having a longitudinal slot communicating with the slots in the arms, a work carrier bar adapted to be slidably disposed in the slots in the arms and to be inserted therein and withdrawn therefrom through the slot in the top plate, a latch adapted to overhang the shorter slot in one of the arms to prevent displacement of the bar therefrom, and a seat rest on the other arm adjustable at an angle to and across the slot therein and forming a support for that-portion of the bar moving through said slot. 1 i 2. A holder for tools to be ground co prising a substantially inverted U-shap e d bracket embodying a top plate and depending arms, said arms being provided with bar receiving slots, a work carrier bar adapted to be slidably disposed in the slots in the arms and to be inserted therein and withdrawn therefrom through the slot in the top plate, a latch adapted to overhang the slot in one of the arms to prevent displacement of the bar therefrom, a pivotally mounted seat rest on the other arm, and means for adjusting said rest at an angle to the slot in said arm so as to provide a support variable as to height for that part of the bar extend ing through said slot.

F 3. A holder for tools to be ground comprising a substantially inverted U-shaped bracket embodying a top plate and depending arms, said arms being provided with bar receiving slots, the slot of one. arm being deeper than the slot of the other arm and the top plate having a longitudinal slot communicating with the slots in the arms, a work carrier bar adapted to be slidably disposed in the slots in the arms and to be inserted therein and withdrawn therefrom through the slot in the top plate, a latch adapted to overhang the shorter slot in one of the arms to prevent displacement of the bar therefrom, a pivotally mountedseat rest on the other arm, and means for adjusting said rest at an angle to the slot in said arm so as to form a variable height support for that portion of the bar extending through said slot.

In testimon whereof I aflix my signature.

CHARLES E. DAVIDSON. 

